Field of the Invention
The present invention relates to a marker for determining the age of beef, comprising p21 protein specific for beef, an antibody specifically binding to bovine p21 protein, a beef-specific kit for determining the age of beef, comprising the antibody specifically binding to bovine p21 protein, and a method for determining beef age, comprising determining the age of beef, using an antigen-antibody binding reaction in which the muscle level of p21 protein is quantitatively analyzed with an antibody specific to bovine p21 protein.
Background Art
With the opening up of the domestic market to beef, South Korea imports a great deal of beef from Canada, the U.S. and other foreign countries. Of the beef imported from North America, such as Canada and the U.S., however, much is from cattle aged over 30 months, which is at great risk for bovine spongiform encephalopathy (BSE), evoking a national concern in South Korea. In fact, 95% of cattle with BSE are known to be over 30 months of age. It is thus required to import beef of less than 30 months of age. However, it is not easy to accurately determine the age of beef.
Currently, the age of beef is determined 1) by a birth certificate or estimated by 2) evaluating the ossification of the bones along the split vertebral column of the carcass or 3) counting the number of permanent incisor teeth in cattle at slaughter. Of these, the most reliable method is the determination made using a birth certificate. On American farms, however, the cattle are generally put out to pasture, so that their birthdays are not accurate. In fact, determining the age using the birth certificate is possible only in as few as 20% of the cattle imported from the U.S. Estimating the age by examining the ossification of the bones, that is, physiological skeletal maturity, is regarded as the most reliable among age determination methods with the naked eye, thus far, but the error rate is as large as about 15%. In addition, the number of teeth in cattle at slaughter is not scientifically accepted as an index for age estimation because the number of teeth greatly varies depending on breeding conditions. Particularly, the teeth-counting method is less accurate for cattle that are put out to pasture because they are not under regulated feeding conditions.
As stated above, currently used methods of determining the age of beef are not accurate, except for using the birth certificate.
Thanks to much study that has been done into determining the origin, grade and maturity of beef, Korean native and imported cattle carcasses can be classified in detail according to the origin, grade and maturity, but the exact age thereof cannot be determined. In addition, examining imported beef using currently used methods requires a great deal of time and expense because of the tremendous amount of such beef.
Therefore, there is a need for a scientific method for accurately determining the age of beef at low cost in a reduced period of time.